The present invention broadly relates to a new and improved construction of a floor cleaning or treatment machine.
In its more specific aspects the present invention relates to a new and improved construction of a floor cleaning or treatment machine possessing at least one rotatably drivable support disc which is driven by means of a motor, such as an electric motor, through a drive train. The support disc holds an exchangeable cleaning or treatment tool or implement.
Conventionally, and depending on the desired floor treatment operation, various cleaning or treatment tools, for example, disc brushes or roller brushes of various grades of hardness, polishing discs or rollers, or even abrasive discs can be fastened to the rotatable support disc of such a machine. Experience has shown that for each of these tools there exists an optimal rotational speed range for each floor treatment operation to be carried out and these ranges of rotational or rotary speed are often different.
Additionally, the surface properties of the floor to be cleaned or treated which, together with the tool being used, are of importance for the resisting moment or torque to be overcome by the motor, i.e. for the operating torque transmitted by the support disc to the tool. Machines of the abovementioned type are now available whose single speed of revolution renders them suitable for only one type of operation. Therefore, with such prior art machines the whole spectrum of desired floor treatment operations cannot be optimally covered.
In order to overcome this disadvantage and also to prevent overloading of the motor or the power supply network feeding it, it has been proposed to install, for example, a two-speed transmission in the drive train between the motor and the support disc or to provide a pole-switchable motor.
Nevertheless, this solution is not satisfactory, since--besides leading to complicated operation--such machines offer only two relatively narrow speed ranges for the support disc, and overloading of the motor is also not entirely precluded.